As an ultra high definition video (for example, 4K requires 15 Mbps to 30 Mbps bandwidth, and 8K requires 100 Mbps to 180 Mbps bandwidth) is gradually popular, when a server provides a streaming media service for a client, a transmission rate requirement of the ultra high definition video cannot be satisfied if only a single transmission path is used. One way to resolve such a problem is to use multiple paths to simultaneously provide a data transmission service for a user. MPTCP (Multipath TCP) is a multipath transmission protocol at a transport layer, and currently, has been in large-scale commercial use in an Apple iOS 7 system. When a transmit end and a receive end include multiple network interfaces (IP addresses), the technology may be used to simultaneously establish multiple sub-streams (TCP links) between different network interfaces to simultaneously send data, so as to improve utilization of idle bandwidth on a network and an end-to-end transmission rate.
SDN (software-defined networking) is a new network innovation architecture, and a core idea of the SDN is to separate a network device control plane from a forwarding plane, so as to flexibly control traffic, and provide an excellent platform for a core network and application innovation. An SDN network includes a network device (for example, a router) and an SDN controller. The SDN controller is configured to: generate a flow table (Flow Table) according to a user configuration or a dynamically running protocol, and send the flow table to the network device. The network device is configured to: receive the flow table from the SDN controller, and match and process a packet according to the flow table.
The prior art (Flow DeMultiplexing Protocol, FDMP) is a technology improved based on MPTCP. The technology uses a network status collection function and a fine transmission path control function of an SDN controller to transmit data between hosts with a single IP address and multiple ports by using multiple streams, and implement accurate control over each sub-stream transmission path, so that path overlapping between multiple sub-streams of a same multi-stream connection is minimum, thereby reducing a possibility that the multiple sub-streams share one transmission path.
However, in the prior art, the SDN controller is overloaded. As a control center of an entire network, the SDN controller not only needs to plan a path for each sub-stream of a multi-stream connection, but also needs to plan a path for another type of connection. Consequently, the SDN controller may become a performance bottleneck of an SDN network.